气候变化领域集成服务门户(CCPortal): Asymmetric response of the subtropical western South Atlantic thermocline to the Dansgaard-Oeschger events of Marine Isotope Stages 5 and 3

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DOI	10.1016/j.quascirev.2020.106307
	Asymmetric response of the subtropical western South Atlantic thermocline to the Dansgaard-Oeschger events of Marine Isotope Stages 5 and 3
	Santos T.P.; Ballalai J.M.; Franco D.R.; Oliveira R.R.; Lessa D.O.; Venancio I.M.; Chiessi C.M.; Kuhnert H.; Johnstone H.; Albuquerque A.L.S.
发表日期	2020
ISSN	0277-3791
卷号	237
英文摘要	The last glacial period (116–11.7 ka BP) was an interval characterized by a sequence of abrupt millennial-scale events well documented in Greenland and Antarctica ice-cores. Throughout this period, Greenland cold stadials were accompanied by warm conditions in the thermocline to intermediate waters of the Atlantic Ocean that may have played a role in both the basal melting of ice shelves and the rapid atmospheric warming during the onset of warm interstadials. Climate model simulations indicated an accentuated response of the subtropical western South Atlantic thermocline to the disturbances in the Atlantic circulation. Such works encourage investigations upon thermocline/deep-dwelling planktic foraminifera in this region; however, a study with this aim was not performed. Here we present a paleoceanographic reconstruction from the subtropical western South Atlantic based on the thermocline planktic foraminifera Globorotalia inflata. Our high-resolution δ18O record for the last glacial period presents a millennial-scale variability that strongly resembles the structure of the Greenland Dansgaard-Oeschger cycles during Marine Isotope Stage (MIS) 5. During MIS 3, this millennial-scale variability is absent or considerably dampened. Mg/Ca-derived temperature and seawater δ18O corrected for ice-volume for the MIS 5 interval demonstrate that the region was warmer and saltier (colder and fresher) during early-glacial stadials (interstadials). Our data suggest a reorganization of the northward heat transport throughout the last glacial, in which regions as far south as 24 °S acted as heat reservoirs in periods of weakened Atlantic Meridional Overturning Circulation during MIS 5 but not necessarily (or only marginally) during MIS 3. © 2020 Elsevier Ltd
英文关键词	Abrupt millennial-scale events; Atlantic meridional overturning circulation; Bipolar seesaw; Climate dynamics; Paleoceanography; South Atlantic central water
语种	英语
scopus关键词	Climate models; Ice; Isotopes; Reservoirs (water); Salinity measurement; Stream flow; Tropics; Asymmetric response; Atlantic meridional overturning circulations; Atmospheric warming; Climate model simulations; Dansgaard-Oeschger cycles; Dansgaard-oeschger events; Marine isotope stages; Planktic foraminifera; Glacial geology; basal melting; calcium; climate modeling; ice core; intermediate water; last glaciation; magnesium; marine isotope stage; oxygen isotope; planktonic foraminifera; seawater; thermocline; warming; water temperature; Atlantic Ocean; Atlantic Ocean (South); Foraminifera; Globorotalia inflata
来源期刊	Quaternary Science Reviews
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/151475
作者单位	Programa de Geociências (Geoquímica), Universidade Federal Fluminense, Niterói, Brazil; Coordenação de Geofísica, Observatório Nacional, Rio de Janeiro, Brazil; Center for Weather Forecasting and Climate Studies (CPTEC), National Institute for Space Research (INPE), Cachoeira Paulista, Brazil; Escola de Artes, Ciências e Humanidades, Universidade de São Paulo, São Paulo, Brazil; MARUM-Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany
推荐引用方式 GB/T 7714	Santos T.P.,Ballalai J.M.,Franco D.R.,et al. Asymmetric response of the subtropical western South Atlantic thermocline to the Dansgaard-Oeschger events of Marine Isotope Stages 5 and 3[J],2020,237.
APA	Santos T.P..,Ballalai J.M..,Franco D.R..,Oliveira R.R..,Lessa D.O..,...&Albuquerque A.L.S..(2020).Asymmetric response of the subtropical western South Atlantic thermocline to the Dansgaard-Oeschger events of Marine Isotope Stages 5 and 3.Quaternary Science Reviews,237.
MLA	Santos T.P.,et al."Asymmetric response of the subtropical western South Atlantic thermocline to the Dansgaard-Oeschger events of Marine Isotope Stages 5 and 3".Quaternary Science Reviews 237(2020).